Sign of the Times
Lessons learned from the Great Hanshin Earthquake
It feels like it was only yesterday, and at the same time, it feels like it was ages ago. Is that how 15 years is supposed to pass by?
Time just passed until that moment, when it was cut off. It was just a matter of coincidence that the person living next door met death and I lived. It was only after 6,434 fellow countrymen had died that time -- a new one -- began to tick once again.
I'd like to share my insights as someone who experienced the Great Hanshin-Awaji Earthquake -- otherwise known as the Kobe earthquake -- with hopes that they will be useful when we confront the next major disaster.
What happens in an earthquake? In the case of tremors under seismic intensity level 5 on the Japan Meteorological Agency (JMA)'s scale with epicenters far away, earthquakes begin with small jarring movements that develop into large rocking. By the time one realizes it's an earthquake and thinks about taking cover, the earthquake is already waning.
Things take a very different course, however, when it comes to earthquakes with seismic intensity of 7, in which the hypocenter is located directly below the epicenter. Our home was suddenly jolted towards the sky. I was ripped out of sleep at 5:46 a.m., and for a moment, did not understand what was happening. Had a plane fallen on our house? Or had we been pounded by a mudslide? The next moment, we were struck by intense horizontal shaking.
It was then that I realized that it was an earthquake, but it was unlike any that I had previously known. It was as if a devil of the earth had our home in its grip and was trying to pull it apart. The house was stretched into a diamond shape, and furniture lurched about. They weren't going to stop until they had destroyed everything. They were here to kill. Why? Why were they killing my family?
It felt like the shaking had continued for two or three minutes, but as it turns out, it lasted only 20 seconds. I couldn't believe it. Records at the Ground Self-Defense Force's Camp Itami in Hyogo Prefecture say, "(everything) shook like a big paper fan." That's how the earthquake appeared some distance away from the epicenter.
Furthermore, a major earthquake in which the hypocenter is some distance away and involves movement of the Nankai plate can potentially cause the two dangers of tsunamis and long-period oscillations. Friends of mine who lived in one of the top floors of a new high-rise in Kobe at the time of the earthquake said that they were tossed from one corner to another of the apartment. Luckily, the building did not snap. But there is a possibility an earthquake originating in the south with long-period oscillations could cause a high-rise building in a large city to resonate.
Had the Kobe earthquake -- in which highways toppled over and elevated bullet train tracks collapsed -- taken place at a time in which the public was out and about, the number of deaths would have been several times higher than it was. In Kobe, 99 percent of people were indoors at the time of the quake, resulting in virtually no casualties outdoors. According to a survey conducted by the then Ministry of Health and Welfare a year after the earthquake, 77 percent of deaths were caused by collapsing residences, 9 percent by fires, and 8 percent by furniture crushing people.
This means that residential durability was what separated approximately 80 percent of those who died from those who survived. The earthquake -- a social experiment, in a sense -- showed surprisingly straightforward results. In areas that recorded a seismic intensity of level 7, most wooden homes were partially or entirely destroyed, comprising most of the deaths.
Reinforced concrete buildings generally survived the quake, but among those that hadn't met newer quake resistance standards, some tilted or buckled. Residents of some buildings were ordered to evacuate. On the other hand, structures made of light materials, such as prefab housing and wood-frame constructions, fared well. They are said to be as strong as cubes whose walls are affixed to each other. In fact, though I thought that I would be killed in the quake, our house remained intact, while we discovered once the sun rose that the mansion of our next-door neighbors had collapsed. Theirs was a traditional Japanese wooden home, and ours was a wood-frame construction.
There are three ways that death can be avoided even when living in a wooden home. First, having reinforcement work done on one's home increases resistance and puts off the house's collapse, allowing its residents to escape instant death.
Second, sleeping in a bed on the second floor of a two-story home can also prove to be a lifesaver. Usually, the first floor of a home collapses diagonally, with the second floor landing on top of it. Sleeping on a bed as opposed to a futon mattress on the floor offers added protection from heavy furniture. (Indeed, all four members of our family survived thanks to this.)
Third, it is important to immobilize furniture to prevent them from turning into weapons. The piano that used to be in the southeast corner of our living room ended up in the northeast corner. We must not underestimate the jolting power of an epicentural earthquake. Seeing as steel trains jumped into the air and derailed without leaving a mark on the tracks, fixing furniture to walls and floors is a definite must.
The three things that we missed dearly moments after the surprise attack were flashlights, slippers, and a transistor radio. Once those first moments had passed, we faced the severe shortage of water, food and toilets.
Even when people find themselves buried under collapsed buildings, those who are blessed with good neighbors often survive. Kansai University Professor Yoshiaki Kawata estimates that 164,000 people were buried under rubble in the Kobe earthquake. Of those, 129,000 people or 79 percent were able to escape on their own. Of the remaining 35,000, 77 percent were rescued by family members and neighbors, highlighting the importance of maintaining good ties with family and community.
The remaining 23 percent were dug out by police, firefighters, and members of the Self-Defense Forces, but waiting for such assistance lowers the chances of survival. Crisis management by government and public agencies has improved since the Kobe earthquake and the SDF is able to mobilize with impressive speed, but over 90 percent of victims must still depend on oneself or others around them to survive.
In the process of collecting oral histories of the Kobe earthquake in the past 15 years, I learned that the rate of rescue differed greatly between areas that had a tradition of holding community festivals and those that did not. People in the 21st century would benefit from once again engaging in the task of community-building. (By Makoto Iokibe, president of the National Defense Academy of Japan)
Click here for the original Japanese story
(Mainichi Japan) February 3, 2010